Someone plz help me with my work?

Question

Find the perimeter and the area of the triangle with the given vertices. Round to the nearest tenth.?
A (2,1)
B (3,6)
C (6,1)

Answer 1

The distance from any point P to Q where P=(x0,y0) and Q=(x1,y1) is given by the formula PQ=sqrt( (x0-x1)^2 + (y0-y1)^2 ). Using this formula,

AB = sqrt( 1 + 25) = sqrt(26)
BC = sqrt( 9 + 25) = sqrt(34)
CA = sqrt( 16+ 0) = 4
So perimiter = 4+sqrt(26)+sqrt(34)

Let A = (x0,y0)
Let B = (x1,y1)
Let C=(x2,y2)

Now AC forms the base of the triangle, since y0=y2. So the area is given by 1/2 * (y1-y0)*(AC) = 1/2 * 5*4 = 10.

Answer 2

The perimeter is the sum of the lengths of the sides. You calculate the lengths with the Pythagorean Theorem. The vertical distance between A and B is 5, the horizontal distance is 1, so the length is root(26) which is 5.1. The vertical distance between B and C is 5, and the horizontal distance is 3, so the length is root(34) which is 5.8. There is no vertical component to the distance between A and C, so the total distance = the horizontal distance = 4. Total Perimeter: 14.9 units.

The area can be calculated by the formula A = (1/2)bh where b is the width of the triangle and h is the height. In this case, the width is 4 and the height is 5, so the area is 10 square units.

Answer 3

First of all plot the points on a diagram.
then the nxt thing you need to do is translate one of the points to (0,0) Translate (2,1) as its closest. Now u must apply this translation to the other two points. E.g watever u did to (2,1) to make it (0,0) do to the other points. (2,1) -(2,1)=(0,0). So (3,6)-(2,1)=? and (6,1)-(2,1) =?
Now, label the two new points you have from above (x1,y1) and (x2,y2).
then apply the formula......

1/2(x1(y2) - x2(y1)) this is the area of the triangle (the answer inside the brackets is ALWAYS a plus numer, if u got a minus u just drop the minus sign!


to get the perimiter you must find the distances between all of the points.
Using the labels A,B,C.
find the distance between A and B
B and C
C and A.
Lable the numbers x1 y1, x2 y2

then apply the formula........distance =


square root of ........(x2-x1)(squared) + (y2-y1)(squared)

remember to be clear on what distances you are calculating. use your diagram.

good luck and i hope that was clear enogh for you to follow!!

Ps. as for the rounding off thing it will probably be clearer when you have your answers as to what you have to do.

Answer 4

Area = 10 from .5(4)(5)

Perimeter is square root of 26 + square root of 34 + 4 = ?

Answer 5

Area = 1/2 * b * h
= 1/2 * 5 * 5
= 12.25 (12.3 rounded)


perimeter = AB + BC+ CA
= sq rt of 21 + 4 + 5
= 4.6 + 4 + 5
13.6